Sanding pads or coated abrasive sheet materials have many useful applications. One particularly useful application may include sanding vehicle body parts of various geometrical shapes and sizes as a preparation for a paint finish. Several factors may impact the efficiency and adequacy of the sanding block, including the grit size of the sandpaper, the size and shape of the pad, and whether the sandpaper is attached to a backing or tool.
One past method of sanding included a user holding a piece of sandpaper in his hands and rubbing it against the surface to be sanded. Many applications require hand sanding where the user will grasp a coated abrasive sheet in his hand and apply it to the surface being treated. However, this method provides an unreliable sanded product as a result of the variable pressure exerted by the user's hands when sanding the object. Improper positioning will cause uneven abrasion of the treated surface. Irregular pressure, such as caused by the fingers against the back side of the abrasive sheet in use, produces an irregular abraded surface.
Another known method of sanding includes the use of a tool developed to aid in the sanding process. Early holding tools or devices used for this purpose were inflexible blocks of solid material such as wood over which the coated abrasive sheet was wrapped. Later a self-adhering coated abrasive sheet material using pressure-sensitive adhesive coated on its back side was developed, so that, it may be adhered directly to the working face of a sanding block. For the most part, this means of attachment assures exposure of the entire abrasive face of the abrasive sheet. Other tools constructed of soft rubber or flexible materials were developed, but because of the flexibility do not provide a consistently uniform finished product because the material deforms as it contacts raised areas in the product being sanded, often causing a washboard effect, ribs, or ripples in the product. The deficiencies encountered by hand-sanding or using a tool must be corrected by the user spending additional and unnecessary time and effort sanding the uneven portions of the product.
A need therefore exists for a sanding tool that operates to provide a material that is rigid enough to not deform against raised areas, but flexible enough to on low spots to provide a consistent, smooth sanded finish on a product.